Weight-conscious consumers who opt for the pre-packaged single portions to more easily control their caloric intake might be achieving the reverse.

The same people who choose these individual snack packets as a way to limit how much they eat, find it more difficult to feel satisfied with just one of the snack-sized portions, and are also more likely have another serving than if there were a full sized bag, according to 2 recent studies published in the Journal of Consumer Research.

The researchers speculate that the actual purchase of multipacks of single-serving snacks may satisfy consumers’ desire to self-regulate their portions, causing them to let their guard down, and leading to a greater quantity consumed than intended.

When consumers were asked about what motivates them to buy different sized packages, the response was as expected: smaller portions were perceived to improve their ability to limit their consumption, where as it was much harder to restrict intake when faced with a larger bag.

In reality, the opposite was true. Among those who were most concerned about portion sizes, consumers ate twice the amount from small packages as compared to a large package, observed the authors. The quantity consumed proved to be lowest when concerns about weight were asked prior to snacking.

It appears that small package formats are perceived as healthier, causing the consumer’s guard to let down, so they feel they do not need to be consious of their eating, and leading to overconsumption.